如何使用SharedPreferences在Android存储，获取和编辑值

我想存储一个时间值，需要检索和编辑它。我如何使用SharedPreferences来做到这一点?

733321 次浏览
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从sharedpreference到编辑数据

 SharedPreferences.Editor editor = getPreferences(MODE_PRIVATE).edit();
editor.putString("text", mSaved.getText().toString());
editor.putInt("selection-start", mSaved.getSelectionStart());
editor.putInt("selection-end", mSaved.getSelectionEnd());
editor.apply();

从sharedpreference到检索数据

SharedPreferences prefs = getPreferences(MODE_PRIVATE);
String restoredText = prefs.getString("text", null);
if (restoredText != null)
{
//mSaved.setText(restoredText, TextView.BufferType.EDITABLE);
int selectionStart = prefs.getInt("selection-start", -1);
int selectionEnd = prefs.getInt("selection-end", -1);
/*if (selectionStart != -1 && selectionEnd != -1)
{
mSaved.setSelection(selectionStart, selectionEnd);
}*/
}

编辑

我从API Demo样本中截取了这个片段。它有一个EditText方框。在这个context中，它不是必需的。我也有同样的看法。

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最佳答案

要获取共享首选项，请使用以下方法 在你的活动中:

SharedPreferences prefs = this.getSharedPreferences(
"com.example.app", Context.MODE_PRIVATE);

读取首选项:

String dateTimeKey = "com.example.app.datetime";


// use a default value using new Date()
long l = prefs.getLong(dateTimeKey, new Date().getTime());

编辑和保存首选项

Date dt = getSomeDate();
prefs.edit().putLong(dateTimeKey, dt.getTime()).apply();

android sdk的示例目录包含一个检索和存储共享首选项的示例。它位于:

<android-sdk-home>/samples/android-<platformversion>/ApiDemos directory

编辑= = >

我注意到，在这里写下commit()和apply()之间的差异也是很重要的。

如果保存成功，则返回true，否则返回false。它将值保存到SharedPreferences 同步。

apply()在2.3中添加，无论成功还是失败都不返回任何值。它会立即将值保存到SharedPreferences，但会启动异步提交。 更多的细节是在这里.

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简单的方法:

保存:

getPreferences(MODE_PRIVATE).edit().putString("Name of variable",value).commit();

检索:

your_variable = getPreferences(MODE_PRIVATE).getString("Name of variable",default value);
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在共享首选项中存储值:

SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("Name","Harneet");
editor.apply();

从共享首选项中检索值:

SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
String name = preferences.getString("Name", "");
if(!name.equalsIgnoreCase(""))
{
name = name + "  Sethi";  /* Edit the value here*/
}
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如何通过SharedPreferences存储登录值的简单解决方案。

您可以扩展MainActivity类或其他存储“想要保留的值”的类。把这些放到作者和读者课程中:

public static final String GAME_PREFERENCES_LOGIN = "Login";

这里InputClass是输入类，OutputClass是输出类。

// This is a storage, put this in a class which you can extend or in both classes:
//(input and output)
public static final String GAME_PREFERENCES_LOGIN = "Login";


// String from the text input (can be from anywhere)
String login = inputLogin.getText().toString();


// then to add a value in InputCalss "SAVE",
SharedPreferences example = getSharedPreferences(GAME_PREFERENCES_LOGIN, 0);
Editor editor = example.edit();
editor.putString("value", login);
editor.commit();

现在你可以在其他地方使用它，比如其他类。下面是OutputClass。

SharedPreferences example = getSharedPreferences(GAME_PREFERENCES_LOGIN, 0);
String userString = example.getString("value", "defValue");


// the following will print it out in console
Logger.getLogger("Name of a OutputClass".class.getName()).log(Level.INFO, userString);
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editor.putString("text", mSaved.getText().toString());

在这里，mSaved可以是任何TextView或EditText，我们可以从中提取一个字符串。您可以简单地指定一个字符串。这里的文本将是保存从mSaved (TextView或EditText)获得的值的键。

SharedPreferences prefs = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);

此外，不需要使用包名保存首选项文件，即“com.example.app”。你可以提到自己喜欢的名字。希望这能有所帮助!

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写:

SharedPreferences preferences = getSharedPreferences("AUTHENTICATION_FILE_NAME", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("Authentication_Id",userid.getText().toString());
editor.putString("Authentication_Password",password.getText().toString());
editor.putString("Authentication_Status","true");
editor.apply();

阅读:

SharedPreferences prfs = getSharedPreferences("AUTHENTICATION_FILE_NAME", Context.MODE_PRIVATE);
String Astatus = prfs.getString("Authentication_Status", "");
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在任何应用程序中，都有可以通过PreferenceManager实例及其相关方法getDefaultSharedPreferences(Context)访问的默认首选项。

使用SharedPreference实例，可以检索使用gettint (String key, int defVal)的任何首选项的int值。在这种情况下，我们更倾向于使用计数器。

在我们的例子中，我们可以使用edit()修改示例中的SharedPreference实例，并使用putInt(String key, int newVal)我们增加了应用程序的计数，这些计数存在于应用程序之外并相应地显示。

为了进一步演示这一点，再次重新启动应用程序，您将注意到每次重新启动应用程序时计数都会增加。

PreferencesDemo.java

代码:

package org.example.preferences;
import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.widget.TextView;


public class PreferencesDemo extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);


// Get the app's shared preferences
SharedPreferences app_preferences =
PreferenceManager.getDefaultSharedPreferences(this);


// Get the value for the run counter
int counter = app_preferences.getInt("counter", 0);


// Update the TextView
TextView text = (TextView) findViewById(R.id.text);
text.setText("This app has been started " + counter + " times.");


// Increment the counter
SharedPreferences.Editor editor = app_preferences.edit();
editor.putInt("counter", ++counter);
editor.commit(); // Very important
}
}

main。xml

代码:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >


<TextView
android:id="@+id/text"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />
</LinearLayout>
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存储信息

SharedPreferences preferences = getSharedPreferences(PREFS_NAME,Context.MODE_PRIVATE);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("username", username.getText().toString());
editor.putString("password", password.getText().toString());
editor.putString("logged", "logged");
editor.commit();

重置您的首选项

SharedPreferences.Editor editor = preferences.edit();
editor.clear();
editor.commit();
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使用这个简单的图书馆，下面是如何调用SharedPreferences..

TinyDB tinydb = new TinyDB(context);


tinydb.putInt("clickCount", 2);


tinydb.putString("userName", "john");
tinydb.putBoolean("isUserMale", true);


tinydb.putList("MyUsers", mUsersArray);
tinydb.putImagePNG("DropBox/WorkImages", "MeAtlunch.png", lunchBitmap);


//These plus the corresponding get methods are all Included
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如果你正在与团队中的其他开发人员一起开发一个大型应用程序，并打算让所有内容都很好地组织起来，而不是分散的代码或不同的SharedPreferences实例，你可以这样做:

//SharedPreferences manager class
public class SharedPrefs {


//SharedPreferences file name
private static String SHARED_PREFS_FILE_NAME = "my_app_shared_prefs";


//here you can centralize all your shared prefs keys
public static String KEY_MY_SHARED_BOOLEAN = "my_shared_boolean";
public static String KEY_MY_SHARED_FOO = "my_shared_foo";


//get the SharedPreferences object instance
//create SharedPreferences file if not present




private static SharedPreferences getPrefs(Context context) {
return context.getSharedPreferences(SHARED_PREFS_FILE_NAME, Context.MODE_PRIVATE);
}


//Save Booleans
public static void savePref(Context context, String key, boolean value) {
getPrefs(context).edit().putBoolean(key, value).commit();
}


//Get Booleans
public static boolean getBoolean(Context context, String key) {
return getPrefs(context).getBoolean(key, false);
}


//Get Booleans if not found return a predefined default value
public static boolean getBoolean(Context context, String key, boolean defaultValue) {
return getPrefs(context).getBoolean(key, defaultValue);
}


//Strings
public static void save(Context context, String key, String value) {
getPrefs(context).edit().putString(key, value).commit();
}


public static String getString(Context context, String key) {
return getPrefs(context).getString(key, "");
}


public static String getString(Context context, String key, String defaultValue) {
return getPrefs(context).getString(key, defaultValue);
}


//Integers
public static void save(Context context, String key, int value) {
getPrefs(context).edit().putInt(key, value).commit();
}


public static int getInt(Context context, String key) {
return getPrefs(context).getInt(key, 0);
}


public static int getInt(Context context, String key, int defaultValue) {
return getPrefs(context).getInt(key, defaultValue);
}


//Floats
public static void save(Context context, String key, float value) {
getPrefs(context).edit().putFloat(key, value).commit();
}


public static float getFloat(Context context, String key) {
return getPrefs(context).getFloat(key, 0);
}


public static float getFloat(Context context, String key, float defaultValue) {
return getPrefs(context).getFloat(key, defaultValue);
}


//Longs
public static void save(Context context, String key, long value) {
getPrefs(context).edit().putLong(key, value).commit();
}


public static long getLong(Context context, String key) {
return getPrefs(context).getLong(key, 0);
}


public static long getLong(Context context, String key, long defaultValue) {
return getPrefs(context).getLong(key, defaultValue);
}


//StringSets
public static void save(Context context, String key, Set<String> value) {
getPrefs(context).edit().putStringSet(key, value).commit();
}


public static Set<String> getStringSet(Context context, String key) {
return getPrefs(context).getStringSet(key, null);
}


public static Set<String> getStringSet(Context context, String key, Set<String> defaultValue) {
return getPrefs(context).getStringSet(key, defaultValue);
}
}

在您的活动中，您可以这样保存SharedPreferences

//saving a boolean into prefs
SharedPrefs.savePref(this, SharedPrefs.KEY_MY_SHARED_BOOLEAN, booleanVar);

你可以这样检索你的SharedPreferences

//getting a boolean from prefs
booleanVar = SharedPrefs.getBoolean(this, SharedPrefs.KEY_MY_SHARED_BOOLEAN);
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SharedPreferences的基本思想是将内容存储在XML文件中。

  1. 声明xml文件路径。(如果你没有这个文件，Android会创建它。如果你有这个文件，Android会访问它。)

    SharedPreferences prefs = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);

  2. Write value to Shared Preferences

    prefs.edit().putLong("preference_file_key", 1010101).apply();

    preference_file_key是共享首选项文件的名称。1010101是您需要存储的值。

    最后使用apply()保存更改。如果从apply()得到错误，则将其更改为commit()。所以这个替代句子是

    prefs.edit().putLong("preference_file_key", 1010101).commit();

  3. Read from Shared Preferences

    SharedPreferences sp = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);
long lsp = sp.getLong("preference_file_key", -1);

    如果preference_file_key没有值，lsp将是-1。如果'preference_file_key'有值，它将返回this的值

整个代码是

    SharedPreferences prefs = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);    // Declare xml file
prefs.edit().putLong("preference_file_key", 1010101).apply();    // Write the value to key.

阅读的代码是

    SharedPreferences sf = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);    // Declare xml file
long lsp = sp.getLong("preference_file_key", -1);    // Read the key and store in lsp
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我想在这里补充一点，当使用SharedPreferences时，这个问题的大多数代码片段都有类似MODE_PRIVATE的东西。MODE_PRIVATE意味着无论您写入这个共享首选项的是什么，都只能由您的应用程序读取。

无论你传递给getSharedPreferences()方法的是什么键，android都会创建一个具有该名称的文件，并将首选项数据存储到其中。 还要记住，getSharedPreferences()应该在您打算为应用程序拥有多个首选项文件时使用。如果您打算使用单个首选项文件并将所有键-值对存储在其中，则使用getSharedPreference()方法。奇怪的是，为什么每个人(包括我自己)都只是简单地使用getSharedPreferences()味道，甚至不理解上面两者之间的区别 下面的视频教程应该会有帮助 # EYZ0 < / p >
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# EYZ0

PreferenceManager.getDefaultSharedPreferences(this).edit().putString("VarName","your value").apply();

收回:

String name = PreferenceManager.getDefaultSharedPreferences(this).getString("VarName","defaultValue");

默认值为:如果该首选项不存在则返回的值。

你可以用< em > getActivity () < / em >或< em > getApplicationContext () < / em >来改变“< em > < / em >” 某些情况下< / p >

小开

人们推荐了许多使用SharedPreferences的方法。我做了一个演示项目在这里。示例中的关键点是使用ApplicationContext,单个sharedpreferences对象。这演示了如何使用SharedPreferences与以下特性

  • 使用singelton类访问/更新SharedPreferences
  • 不需要总是为读/写SharedPreferences传递上下文
  • 它使用apply()而不是commit()
  • apply()是异步保存，不返回任何东西，它首先更新内存中的值&稍后将更改写入磁盘 李asynchronusly。< / >
  • Commit()是同步保存，它根据结果返回true/false。更改以同步方式写入磁盘
  • 适用于android 2.3+版本

使用示例如下:-

MyAppPreference.getInstance().setSampleStringKey("some_value");
String value= MyAppPreference.getInstance().getSampleStringKey();

点击这里获取源代码 ,详细的API可以在developer.android.com找到这里<强> < / >强

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存储在SharedPreferences中

SharedPreferences preferences = getSharedPreferences("temp", getApplicationContext().MODE_PRIVATE);
Editor editor = preferences.edit();
editor.putString("name", name);
editor.commit();

获取SharedPreferences

SharedPreferences preferences=getSharedPreferences("temp", getApplicationContext().MODE_PRIVATE);
String name=preferences.getString("name",null);

注:“temp”为sharedpreferences名称，“name”为输入值。如果value不存在，则返回null

小开

您可以使用以下方法保存值:

public void savePreferencesForReasonCode(Context context,
String key, String value) {
SharedPreferences sharedPreferences = PreferenceManager
.getDefaultSharedPreferences(context);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(key, value);
editor.commit();
}

使用这个方法，你可以从SharedPreferences中获取值:

public String getPreferences(Context context, String prefKey) {
SharedPreferences sharedPreferences = PreferenceManager
.getDefaultSharedPreferences(context);
return sharedPreferences.getString(prefKey, "");
}

这里prefKey是用来保存特定值的键。谢谢。

小开

最好的实践

创建名为PreferenceManager的接口:

// Interface to save values in shared preferences and also for retrieve values from shared preferences
public interface PreferenceManager {


SharedPreferences getPreferences();
Editor editPreferences();


void setString(String key, String value);
String getString(String key);


void setBoolean(String key, boolean value);
boolean getBoolean(String key);


void setInteger(String key, int value);
int getInteger(String key);


void setFloat(String key, float value);
float getFloat(String key);


}

如何使用活动 / 片段:

public class HomeActivity extends AppCompatActivity implements PreferenceManager{


@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout_activity_home);
}


@Override
public SharedPreferences getPreferences(){
return getSharedPreferences("SP_TITLE", Context.MODE_PRIVATE);
}


@Override
public SharedPreferences.Editor editPreferences(){
return getPreferences().edit();
}


@Override
public void setString(String key, String value) {
editPreferences().putString(key, value).commit();
}


@Override
public String getString(String key) {
return getPreferences().getString(key, "");
}


@Override
public void setBoolean(String key, boolean value) {
editPreferences().putBoolean(key, value).commit();
}


@Override
public boolean getBoolean(String key) {
return  getPreferences().getBoolean(key, false);
}


@Override
public void setInteger(String key, int value) {
editPreferences().putInt(key, value).commit();
}


@Override
public int getInteger(String key) {
return getPreferences().getInt(key, 0);
}


@Override
public void setFloat(String key, float value) {
editPreferences().putFloat(key, value).commit();
}


@Override
public float getFloat(String key) {
return getPreferences().getFloat(key, 0);
}
}

将您的SharedPreference键替换为SP_TITLE。

例子:

shareperence中的存储字符串:

setString("my_key", "my_value");

得到字符串从shareperence:

String strValue = getString("my_key");

希望这对你有所帮助。

小开

简单和无麻烦::"Android-SharedPreferences-Helper"库

迟到总比不到好:我创建了“Android-SharedPreferences-Helper”库来帮助减少使用SharedPreferences的复杂性和工作量。它还提供了一些扩展功能。它提供的一些东西如下:

  • 一行初始化和设置
  • 轻松选择是使用默认首选项还是自定义首选项文件
  • 每种数据类型的预定义(默认数据类型)和自定义(您可以选择的)默认值
  • 能力设置不同的默认值为单一使用，只是一个额外的参数
  • 你可以注册和取消注册OnSharedPreferenceChangeListener，因为你做的默认类
dependencies {
...
...
compile(group: 'com.viralypatel.sharedpreferenceshelper', name: 'library', version: '1.1.0', ext: 'aar')
}

SharedPreferencesHelper对象的声明:(在类中推荐 级)< / p > 

SharedPreferencesHelper sph;

SharedPreferencesHelper对象的实例化:(建议在 onCreate()方法)< / p > 

// use one of the following ways to instantiate
sph = new SharedPreferencesHelper(this); //this will use default shared preferences
sph = new SharedPreferencesHelper(this, "myappprefs"); // this will create a named shared preference file
sph = new SharedPreferencesHelper(this, "myappprefs", 0); // this will allow you to specify a mode

将价值观融入到共同的偏好中

非常简单!不像默认的方式(当使用SharedPreferences类)，你不需要调用.edit()和.commit()任何时候。

sph.putBoolean("boolKey", true);
sph.putInt("intKey", 123);
sph.putString("stringKey", "string value");
sph.putLong("longKey", 456876451);
sph.putFloat("floatKey", 1.51f);


// putStringSet is supported only for android versions above HONEYCOMB
Set name = new HashSet();
name.add("Viral");
name.add("Patel");
sph.putStringSet("name", name);

就是这样!您的值存储在共享首选项中。

从共享首选项中获取值

同样，这只是一个使用键名的简单方法调用。

sph.getBoolean("boolKey");
sph.getInt("intKey");
sph.getString("stringKey");
sph.getLong("longKey");
sph.getFloat("floatKey");


// getStringSet is supported only for android versions above HONEYCOMB
sph.getStringSet("name");

它还有很多其他扩展功能

在GitHub存储库页面上查看扩展功能的详细信息，使用和安装说明等。

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在这里，我创建了一个Helper类来使用android中的首选项。

这是helper类:

public class PrefsUtil {


public static SharedPreferences getPreference() {
return PreferenceManager.getDefaultSharedPreferences(Applicatoin.getAppContext());
}


public static void putBoolean(String key, boolean value) {
getPreference().edit().putBoolean(key, value)
.apply();
}


public static boolean getBoolean(String key) {
return getPreference().getBoolean(key, false);
}


public static void putInt(String key, int value) {


getPreference().edit().putInt(key, value).apply();


}


public static void delKey(String key) {


getPreference().edit().remove(key).apply();


}


}
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以函数的方式存储和检索全局变量。 要测试，请确保页面上有Textview项，取消代码中的两行注释并运行。然后再次注释这两行，并运行。
这里TextView的id是用户名和密码 在你想要使用它的每个Class中，在最后添加这两个例程。 我想这个例行程序是全球例行程序，但不知道如何。这工作。< / p >

变量在任何地方都可用。 它将变量存储在“MyFile”中。

你称之为使用

 storeSession("username","frans");
storeSession("password","!2#4%");***

变量username将用“frans”填充，密码为“!2#4%”。即使在重新启动后，它们仍然可用。

你用

 password.setText(getSession(("password")));
usernames.setText(getSession(("username")));

下面是我的grid.java的全部代码

    package nl.yentel.yenteldb2;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;


public class Grid extends AppCompatActivity {
private TextView usernames;
private TextView password;


@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_grid);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);


FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
getSupportActionBar().setDisplayHomeAsUpEnabled(true);


***//  storeSession("username","frans.eilering@gmail.com");
//storeSession("password","mijn wachtwoord");***
password = (TextView) findViewById(R.id.password);
password.setText(getSession(("password")));
usernames=(TextView) findViewById(R.id.username);
usernames.setText(getSession(("username")));
}


public void storeSession(String key, String waarde) {
SharedPreferences pref = getApplicationContext().getSharedPreferences("MyFile", MODE_PRIVATE);
SharedPreferences.Editor editor = pref.edit();
editor.putString(key, waarde);
editor.commit();
}


public String getSession(String key) {
//http://androidexample.com/Android_SharedPreferences_Basics/index.php?view=article_discription&aid=126&aaid=146
SharedPreferences pref = getApplicationContext().getSharedPreferences("MyFile", MODE_PRIVATE);
SharedPreferences.Editor editor = pref.edit();
String output = pref.getString(key, null);
return output;
}


}

下面是textview项

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="usernames"
android:id="@+id/username"
android:layout_below="@+id/textView"
android:layout_alignParentStart="true"
android:layout_marginTop="39dp"
android:hint="hier komt de username" />


<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="password"
android:id="@+id/password"
android:layout_below="@+id/user"
android:layout_alignParentStart="true"
android:hint="hier komt het wachtwoord" />
小开

单例共享首选项类。这可能对将来的其他人有所帮助。

import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;


public class SharedPref
{
private static SharedPreferences mSharedPref;
public static final String NAME = "NAME";
public static final String AGE = "AGE";
public static final String IS_SELECT = "IS_SELECT";


private SharedPref()
{


}


public static void init(Context context)
{
if(mSharedPref == null)
mSharedPref = context.getSharedPreferences(context.getPackageName(), Activity.MODE_PRIVATE);
}


public static String read(String key, String defValue) {
return mSharedPref.getString(key, defValue);
}


public static void write(String key, String value) {
SharedPreferences.Editor prefsEditor = mSharedPref.edit();
prefsEditor.putString(key, value);
prefsEditor.commit();
}


public static boolean read(String key, boolean defValue) {
return mSharedPref.getBoolean(key, defValue);
}


public static void write(String key, boolean value) {
SharedPreferences.Editor prefsEditor = mSharedPref.edit();
prefsEditor.putBoolean(key, value);
prefsEditor.commit();
}


public static Integer read(String key, int defValue) {
return mSharedPref.getInt(key, defValue);
}


public static void write(String key, Integer value) {
SharedPreferences.Editor prefsEditor = mSharedPref.edit();
prefsEditor.putInt(key, value).commit();
}
}

只需在MainActivity上调用SharedPref.init()一次

SharedPref.init(getApplicationContext());

写入数据

SharedPref.write(SharedPref.NAME, "XXXX");//save string in shared preference.
SharedPref.write(SharedPref.AGE, 25);//save int in shared preference.
SharedPref.write(SharedPref.IS_SELECT, true);//save boolean in shared preference.

读取数据

String name = SharedPref.read(SharedPref.NAME, null);//read string in shared preference.
int age = SharedPref.read(SharedPref.AGE, 0);//read int in shared preference.
boolean isSelect = SharedPref.read(SharedPref.IS_SELECT, false);//read boolean in shared preference.
小开

我为sharedpreferences写了一个helper类:

import android.content.Context;
import android.content.SharedPreferences;


/**
* Created by mete_ on 23.12.2016.
*/
public class HelperSharedPref {


Context mContext;


public HelperSharedPref(Context mContext) {
this.mContext = mContext;
}


/**
*
* @param key Constant RC
* @param value Only String, Integer, Long, Float, Boolean types
*/
public void saveToSharedPref(String key, Object value) throws Exception {
SharedPreferences.Editor editor = mContext.getSharedPreferences(key, Context.MODE_PRIVATE).edit();
if (value instanceof String) {
editor.putString(key, (String) value);
} else if (value instanceof Integer) {
editor.putInt(key, (Integer) value);
} else if (value instanceof Long) {
editor.putLong(key, (Long) value);
} else if (value instanceof Float) {
editor.putFloat(key, (Float) value);
} else if (value instanceof Boolean) {
editor.putBoolean(key, (Boolean) value);
} else {
throw new Exception("Unacceptable object type");
}


editor.commit();
}


/**
* Return String
* @param key
* @return null default is null
*/
public String loadStringFromSharedPref(String key) throws Exception {
SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
String restoredText = prefs.getString(key, null);


return restoredText;
}


/**
* Return int
* @param key
* @return null default is -1
*/
public Integer loadIntegerFromSharedPref(String key) throws Exception {
SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
Integer restoredText = prefs.getInt(key, -1);


return restoredText;
}


/**
* Return float
* @param key
* @return null default is -1
*/
public Float loadFloatFromSharedPref(String key) throws Exception {
SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
Float restoredText = prefs.getFloat(key, -1);


return restoredText;
}


/**
* Return long
* @param key
* @return null default is -1
*/
public Long loadLongFromSharedPref(String key) throws Exception {
SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
Long restoredText = prefs.getLong(key, -1);


return restoredText;
}


/**
* Return boolean
* @param key
* @return null default is false
*/
public Boolean loadBooleanFromSharedPref(String key) throws Exception {
SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
Boolean restoredText = prefs.getBoolean(key, false);


return restoredText;
}


}
小开

我创建了一个Helper类来简化我的生活。这是一个泛型类，有很多在应用程序中常用的方法，如共享首选项，电子邮件有效性，日期时间格式。在代码中复制这个类，并在任何需要的地方访问它的方法。

 import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.SharedPreferences;
import android.support.v4.app.FragmentActivity;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;
import android.widget.Toast;


import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Random;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;


/**
* Created by Zohaib Hassan on 3/4/2016.
*/
public class Helper {


private static ProgressDialog pd;


public static void saveData(String key, String value, Context context) {
SharedPreferences sp = context.getApplicationContext()
.getSharedPreferences("appData", 0);
SharedPreferences.Editor editor;
editor = sp.edit();
editor.putString(key, value);
editor.commit();
}


public static void deleteData(String key, Context context){
SharedPreferences sp = context.getApplicationContext()
.getSharedPreferences("appData", 0);
SharedPreferences.Editor editor;
editor = sp.edit();
editor.remove(key);
editor.commit();


}


public static String getSaveData(String key, Context context) {
SharedPreferences sp = context.getApplicationContext()
.getSharedPreferences("appData", 0);
String data = sp.getString(key, "");
return data;


}








public static long dateToUnix(String dt, String format) {
SimpleDateFormat formatter;
Date date = null;
long unixtime;
formatter = new SimpleDateFormat(format);
try {
date = formatter.parse(dt);
} catch (Exception ex) {


ex.printStackTrace();
}
unixtime = date.getTime();
return unixtime;


}


public static String getData(long unixTime, String formate) {


long unixSeconds = unixTime;
Date date = new Date(unixSeconds);
SimpleDateFormat sdf = new SimpleDateFormat(formate);
String formattedDate = sdf.format(date);
return formattedDate;
}


public static String getFormattedDate(String date, String currentFormat,
String desiredFormat) {
return getData(dateToUnix(date, currentFormat), desiredFormat);
}








public static double distance(double lat1, double lon1, double lat2,
double lon2, char unit) {
double theta = lon1 - lon2;
double dist = Math.sin(deg2rad(lat1)) * Math.sin(deg2rad(lat2))
+ Math.cos(deg2rad(lat1)) * Math.cos(deg2rad(lat2))
* Math.cos(deg2rad(theta));
dist = Math.acos(dist);
dist = rad2deg(dist);
dist = dist * 60 * 1.1515;
if (unit == 'K') {
dist = dist * 1.609344;
} else if (unit == 'N') {
dist = dist * 0.8684;
}
return (dist);
}


/* ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: */
/* :: This function converts decimal degrees to radians : */
/* ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: */
private static double deg2rad(double deg) {
return (deg * Math.PI / 180.0);
}


/* ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: */
/* :: This function converts radians to decimal degrees : */
/* ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: */
private static double rad2deg(double rad) {
return (rad * 180.0 / Math.PI);
}


public static int getRendNumber() {
Random r = new Random();
return r.nextInt(360);
}


public static void hideKeyboard(Context context, EditText editText) {
InputMethodManager imm = (InputMethodManager) context
.getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(editText.getWindowToken(), 0);
}


public static void showLoder(Context context, String message) {
pd = new ProgressDialog(context);


pd.setCancelable(false);
pd.setMessage(message);
pd.show();
}


public static void showLoderImage(Context context, String message) {
pd = new ProgressDialog(context);
pd.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
pd.setCancelable(false);
pd.setMessage(message);
pd.show();
}


public static void dismissLoder() {
pd.dismiss();
}


public static void toast(Context context, String text) {


Toast.makeText(context, text, Toast.LENGTH_LONG).show();
}
/*
public static Boolean connection(Context context) {
ConnectionDetector connection = new ConnectionDetector(context);
if (!connection.isConnectingToInternet()) {


Helper.showAlert(context, "No Internet access...!");
//Helper.toast(context, "No internet access..!");
return false;
} else
return true;
}*/


public static void removeMapFrgment(FragmentActivity fa, int id) {


android.support.v4.app.Fragment fragment;
android.support.v4.app.FragmentManager fm;
android.support.v4.app.FragmentTransaction ft;
fm = fa.getSupportFragmentManager();
fragment = fm.findFragmentById(id);
ft = fa.getSupportFragmentManager().beginTransaction();
ft.remove(fragment);
ft.commit();


}


public static AlertDialog showDialog(Context context, String message) {
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setMessage(message);


builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {


@Override
public void onClick(DialogInterface dialog, int id) {
// TODO Auto-generated method stub


}
});


return builder.create();
}


public static void showAlert(Context context, String message) {
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setTitle("Alert");
builder.setMessage(message)
.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.dismiss();
}
}).show();
}


public static boolean isURL(String url) {
if (url == null)
return false;


boolean foundMatch = false;
try {
Pattern regex = Pattern
.compile(
"\\b(?:(https?|ftp|file)://|www\\.)?[-A-Z0-9+&#/%?=~_|$!:,.;]*[A-Z0-9+&@#/%=~_|$]\\.[-A-Z0-9+&@#/%?=~_|$!:,.;]*[A-Z0-9+&@#/%=~_|$]",
Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE);
Matcher regexMatcher = regex.matcher(url);
foundMatch = regexMatcher.matches();
return foundMatch;
} catch (PatternSyntaxException ex) {
// Syntax error in the regular expression
return false;
}
}


public static boolean atLeastOneChr(String string) {
if (string == null)
return false;


boolean foundMatch = false;
try {
Pattern regex = Pattern.compile("[a-zA-Z0-9]",
Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE);
Matcher regexMatcher = regex.matcher(string);
foundMatch = regexMatcher.matches();
return foundMatch;
} catch (PatternSyntaxException ex) {
// Syntax error in the regular expression
return false;
}
}


public static boolean isValidEmail(String email, Context context) {
String expression = "^[\\w\\.-]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";
CharSequence inputStr = email;
Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);
Matcher matcher = pattern.matcher(inputStr);
if (matcher.matches()) {
return true;
} else {
// Helper.toast(context, "Email is not valid..!");


return false;
}
}


public static boolean isValidUserName(String email, Context context) {
String expression = "^[0-9a-zA-Z]+$";
CharSequence inputStr = email;
Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);
Matcher matcher = pattern.matcher(inputStr);
if (matcher.matches()) {
return true;
} else {
Helper.toast(context, "Username is not valid..!");
return false;
}
}


public static boolean isValidDateSlash(String inDate) {
SimpleDateFormat dateFormat = new SimpleDateFormat("dd/mm/yyyy");
dateFormat.setLenient(false);
try {
dateFormat.parse(inDate.trim());
} catch (ParseException pe) {
return false;
}
return true;
}


public static boolean isValidDateDash(String inDate) {
SimpleDateFormat dateFormat = new SimpleDateFormat("dd-mm-yyyy");
dateFormat.setLenient(false);
try {
dateFormat.parse(inDate.trim());
} catch (ParseException pe) {
return false;
}
return true;
}


public static boolean isValidDateDot(String inDate) {
SimpleDateFormat dateFormat = new SimpleDateFormat("dd.mm.yyyy");
dateFormat.setLenient(false);
try {
dateFormat.parse(inDate.trim());
} catch (ParseException pe) {
return false;
}
return true;
}


}
小开

编辑

SharedPreferences pref = getSharedPreferences("YourPref", MODE_PRIVATE);
SharedPreferences.Editor editor = pref.edit();
editor.putString("yourValue", value);
editor.commit();

读

SharedPreferences pref = getSharedPreferences("YourPref", MODE_PRIVATE);
value= pref.getString("yourValue", "");
小开

在共享首选项中存储值:

SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = sp.edit();
editor.putString("Name","Jayesh");
editor.commit();

从共享首选项中检索值:

SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
String name = sp.getString("Name", "");
小开

使用使用这个例子简单明了和检查

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.sairamkrishna.myapplication" >


<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >


<activity
android:name=".MainActivity"
android:label="@string/app_name" >


<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>


</activity>


</application>
</manifest>

public class MainActivity extends AppCompatActivity {
EditText ed1,ed2,ed3;
Button b1;


public static final String MyPREFERENCES = "MyPrefs" ;
public static final String Name = "nameKey";
public static final String Phone = "phoneKey";
public static final String Email = "emailKey";


SharedPreferences sharedpreferences;


@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);


ed1=(EditText)findViewById(R.id.editText);
ed2=(EditText)findViewById(R.id.editText2);
ed3=(EditText)findViewById(R.id.editText3);


b1=(Button)findViewById(R.id.button);
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);


b1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String n  = ed1.getText().toString();
String ph  = ed2.getText().toString();
String e  = ed3.getText().toString();


SharedPreferences.Editor editor = sharedpreferences.edit();


editor.putString(Name, n);
editor.putString(Phone, ph);
editor.putString(Email, e);
editor.commit();
Toast.makeText(MainActivity.this,"Thanks",Toast.LENGTH_LONG).show();
}
});
}


}
小开 
SharedPreferences.Editor editor = getSharedPreferences("identifier",
MODE_PRIVATE).edit();
//identifier is the unique to fetch data from your SharedPreference.




editor.putInt("keyword", 0);
// saved value place with 0.
//use this "keyword" to fetch saved value again.
editor.commit();//important line without this line your value is not stored in preference


// fetch the stored data using ....


SharedPreferences prefs = getSharedPreferences("identifier", MODE_PRIVATE);
// here both identifier will same


int fetchvalue = prefs.getInt("keyword", 0);
// here keyword will same as used above.
// 0 is default value when you nothing save in preference that time fetch value is 0.

你需要在适配器类或任何其他中使用SharedPreferences。 这一次只需要使用这个声明并使用上面相同的ass 

SharedPreferences.Editor editor = context.getSharedPreferences("idetifier",
Context.MODE_PRIVATE).edit();
SharedPreferences prefs = context.getSharedPreferences("identifier", Context.MODE_PRIVATE);


//here context is your application context

用于字符串或布尔值

editor.putString("stringkeyword", "your string");
editor.putBoolean("booleankeyword","your boolean value");
editor.commit();

取数据与上面相同

String fetchvalue = prefs.getString("keyword", "");
Boolean fetchvalue = prefs.getBoolean("keyword", "");
小开

在共享首选项中存储值:

SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = sp.edit();
editor.putString("Name","Jayesh");
editor.commit();

从共享首选项中检索值:

SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
String name = sp.getString("Name", ""); // Second parameter is the default value.
小开

2.用于存储在共享优先级

SharedPreferences.Editor editor =
getSharedPreferences("DeviceToken",MODE_PRIVATE).edit();
editor.putString("DeviceTokenkey","ABABABABABABABB12345");
editor.apply();

2.用于检索相同的用途

    SharedPreferences prefs = getSharedPreferences("DeviceToken",
MODE_PRIVATE);
String deviceToken = prefs.getString("DeviceTokenkey", null);

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